Known as a lighting device used by attachment to a ceiling has been a suspending-type (or referred to also as pendant-type) lighting device that is disclosed in, for example, Patent Document 1 (Japanese Patent Application Laid-open No. H5-109309) and that is used by utilizing a power supply line preliminarily attached to the ceiling and by being suspended from the ceiling. Moreover, a technique for attaching, to a ceiling light, a communication functional module that is capable of utilizing various functions and that is attached to a ceiling or a wall surface has been disclosed Patent Document 2 (Japanese Patent Application Laid-open No. 2003-16831).